Tongue-palatal contact changes in patients with skeletal mandibular prognathism after sagittal split ramus osteotomy: an electropalatography study.

The purpose of this study was to investigate the changes in tongue-palatal contact patterns using electropalatography (EPG) before and after sagittal split ramus osteotomy (SSRO) in patients with mandibular prognathism. Nine clients who underwent SSRO for mandibular setback and seven control subjects were participated in this study. Tongue-palatal contact patterns for /t/, /s/ and /k/ production were investigated using EPG before surgery and 3 months after surgery. The mean value of whole total of palate contact (WT) in the maximum contact frame was examined before and after SSRO. The correlation quantity between the change of center of gravity (COG) value and the amount of mandibular setback was also evaluated. The mean value of WT for /t/ and /s/ significantly increased after SSRO, and the EPG pattern became normal. However, a remarkable change in WT for /k/ was not observed, and the mean value was significantly larger in the SSRO group before and after surgery than in the control group. A negative correlation between COG variation and the amount of mandibular setback for /t/ and positive correlation for /s/ was observed. This study demonstrated that tongue-palatal contact patterns for /t/ and /s/ articulation improved clearly after SSRO. There was a significant correlation between COG variation and the amount of mandibular setback. However, no significant change was detected through perceptual assessment before and after SSRO. Further investigation is needed to determine whether these results will change over time.

Effects of storage temperature on the shelf life of one-step and two-step self-etch adhesives.

Recently, self-etch adhesive systems, the one-step (all-in-one) and two-step adhesive systems, have become widely utilized due to their simplified application procedures and low technique sensitivity. In the current study, in order to understand the effects on shelf life of the two types of self-etch adhesives, the effects from storage temperature and time period on the alteration stage of 10-methacryloxydecyl dihydrogen phosphate (MDP)-based, a one-step adhesive (all-in-one adhesive system) and an MDP-based self-etching primer (two-step adhesive system) were examined. Clearfil Tri-S Bond (TSB), an MDP-based one-step adhesive (all-in-one adhesive system), and Clearfil Mega Bond Primer (MBP), an MDP-based self-etching primer (two-step adhesive system), were used. Both TSB and MBP, received within two days after they were produced, were immediately stored at 8 degrees C, 20 degrees C or 40 degrees C for 1, 3, 7 and 14 weeks, respectively. At the end of each storage period, 13C NMR observations were performed by an EX-270 spectrometer. In addition, NMR observations of TSB and MBP were immediately performed within two days, after both were produced as a control. The effects from the storage temperature and time period on the alteration rate and stage of TSB and MBP were examined by determining the amount of hydrolyzed 2-hydroxyethyl methacrylate (HEMA) and MDP in both materials. Specimens bonded to dentin by using TSB or MBP in different alteration stages were prepared. The degradation stage effect of TSB or MBP on bond durability was examined by measuring the shear bond strength before and after thermocycling (20,000 times). With increases in storage temperature and time period, the relative intensities of the NMR peak "epsilon" assigned to both methylene carbons in the ethylene glycol (EG) and to the NMR peak "zeta" assigned to the terminal methylene carbon bonded to the hydroxy group in the 10-hydroxydecyl dihydrogen phosphate (HDP) produced by the hydrolysis of the ester portion in HEMA or MDP, respectively, increased. The alteration stages of TSB and MBP were strongly dependent on storage temperature and time period. When TSB or MBP, stored at 40 degrees C for 14 weeks, was applied to dentin, specific decreases in mean bond strength were observed in both adhesive systems. However, the application of thermocycling did not exhibit any specific decreases in the mean bond strength, even though the alteration stage of TSB and MBP progressed. From the results of the current study, storage temperature and time period significantly affect the alteration rate and stage of TSB and MBP. However, TSB and MBP exhibit expectant bond strength and bond durability when both are stored below 20 degrees C.

Periodontal tissue engineering by transplantation of multilayered sheets of phenotypically modified gingival fibroblasts.

BACKGROUND AND OBJECTIVE: In periodontal tissue engineering, the sourcing of most of the relevant cells is limited by poor accessibility, whereas the use of readily available gingival fibroblasts is hampered because of their inhibitory effects on bone formation. To address the latter drawback, we developed a new graft composed of fibronectin (FN) matrix-based multilayered cell sheets of human gingival fibroblasts modified to express alkaline phosphatase (ALP). This study was undertaken to investigate the effects of this graft, called the FN-ALP transplant, on the healing of periodontal defects in a rat model. MATERIAL AND METHODS: The FN-ALP transplants were grafted into periodontal fenestration bone defects in immunosuppressed rats. The process of periodontal healing was examined by histology, histomorphometry and immunohistochemistry. Grafted cells were tracked by immunostaining with human-specific antibodies. Control groups included non-transplanted empty defects and defects to which cell sheets without ALP induction had been grafted. RESULTS: After implantation, the FN-ALP transplants healed alveolar bone defects by intramembranous ossification, with formation of cementum and periodontal ligament. Moreover, FN-ALP transplants increased new bone formation, by endochondral ossification, on the mandibular cortex adjacent to the defect. Grafted fibroblasts were located near host osteoblasts and chondrocyte precursor cells early in the ossification process but were undetectable on and in newly formed bone and cartilage. CONCLUSION: These results indicate that the FN-ALP transplants support alveolar bone regeneration within the defect and augment bone formation outside the defect through the recruitment of host osteo/chondrogenic cells, suggesting their potential for periodontal tissue engineering applications.

Plasminogen-binding protein associated with the plasma membrane of cultured embryonic rat neocortical neurons.

To investigate the receptor-like molecule(s) for plasminogen (PGn) on the neuronal surface, the properties of binding of PGn to the plasma membrane of cultured embryonic rat neocortical neurons were investigated. [125I]PGn was found to specifically bind to the plasma membrane depending on the incubation temperature and time. The binding was also affected strongly by ionic strength and slightly by Ca2+. Furthermore, ligand blotting analysis revealed that [125I]PGn binds to a major protein with an apparent molecular weight of 45 kDa among plasma membrane proteins. These results suggest that the 45-kDa protein is a PGn receptor-like molecule on the neuronal surface.

Scleral plug of biodegradable polymers containing ganciclovir for experimental cytomegalovirus retinitis.

PURPOSE: To evaluate the efficacy of a biodegradable scleral plug containing ganciclovir (GCV) in a rabbit model of human cytomegalovirus (HCMV) retinitis. METHODS: To develop a rabbit model for HCMV retinitis, HCMV solution was injected once into the vitreous cavity of pigmented rabbits. The treated animals were divided into three groups: group A received no treatment, group B was treated once with GCV solution, and group C was treated with a scleral plug containing GCV. Rabbits in group B received an intravitreal injection of GCV solution 1 week after HCMV inoculation. In group C, the scleral plug containing GCV was implanted in the vitreous of the rabbits 1 week after HCMV inoculation. Ophthalmoscopically, vitreoretinal findings in each group were graded from 0+ to 4+ every week for 4 weeks after HCMV injection. RESULTS: Eyes of group A rabbits showed whitish retinal exudates and vitreous opacities 3 days after HCMV inoculation. These materials increased gradually until 3 weeks after HCMV inoculation. Scores for vitreoretinal lesions were significantly lower in eyes of group B rabbits compared with those of group A at 1 week after GCV injection (P < 0.05). However, vitreoretinal inflammation in eyes of group B rabbits increased again thereafter, and no significant difference in inflammation between groups A and B was found 2 weeks after GCV injection. In eyes of group C, scores for vitreoretinal lesions were significantly lower compared with those in both group A and group B at 3 weeks after HCMV inoculation (P < 0.01). CONCLUSIONS: The results demonstrated that sustained release of GCV into the vitreous cavity with biodegradable scleral plugs was effective for the treatment of experimentally induced HCMV retinitis in rabbits.

Use of inorganic salts to minimize serum interference in a sandwich enzyme immunoassay for human growth hormone using Fab'-horseradish peroxidase conjugate.

In a sandwich enzyme immunoassay (EIA) for human growth hormone (hGH) with anti-hGH Fab'-peroxidase conjugate, the effects of inorganic salts on serum interference were examined, and serum interference was eliminated by incubation of serum samples with anti-hGH IgG-coated polystyrene balls in the presence of 0.4 mol/l NaCl, avoiding the need for hGH-free serum. The sensitivity for hGH was 60 fg/tube or 3 ng/l of serum. No cross-reaction was observed with prolactin, chorionic gonadotropin or luteinizing, thyroid-stimulating and follicle-stimulating hormones. The coefficients of within-assay and between-assay variations were 2.8-6.5% and 4.8-8.7%, respectively. The regression equation and correlation coefficient to radioimmunoassay (RIA) were y(EIA) = 0.89x(RIA) + 0.11 and 0.98 (n = 100), respectively. hGH levels in normal male and female adult serum taken between 9:00 and 10:00 a.m. after overnight fasting and 1 h rest were 312 ng/l (range 53-940 ng/l; n = 10) and 662 ng/l (112-2195 ng/l; n = 13), respectively.

A more sensitive and less time-consuming sandwich enzyme immunoassay for insulin in human serum with less serum interference.

This paper describes an improved sandwich enzyme immunoassay for insulin in human serum. The detection limit was significantly improved from 0.1 mU/L to 0.02 mU/L, by incubation with guinea-pig anti-insulin Fab'-peroxidase conjugate in the presence of normal guinea-pig F(ab')2 to reduce the non-specific binding of the conjugate. The degree of serum interference was considerably reduced by coating polystyrene balls with acid-treated anti-insulin IgG and by incubating the polystyrene balls with serum samples at a lower temperature for a shorter time. The time for incubation with anti-insulin Fab'-peroxidase conjugate was also shortened. As a result, the volume of serum that could be used increased from 10 microliters to 50 microliters, and the time for immuno-reactions was reduced from 8 h to 4 h. Applicability of the present improvement to enzyme immunoassay of other antigens in human serum is discussed.

Oral health habits and the number of teeth present in Japanese aged 50-80 years.

OBJECTIVE: To suggest appropriate oral health habits for daily practice in order to prevent tooth loss. DESIGN: Cross sectional study correlating mean number of teeth and oral health habits. SETTING: All 97 dental clinics in an urban area (population 256,000) in Osaka Prefecture, Japan. SUBJECTS: 1,248 persons aged 50-80 who received dental treatment at any of the dental clinics between 10 January and 7 February, 1992. OUTCOME MEASURES: The number of teeth present was recorded by the dentists in their clinics. The subjects were asked to complete questionnaires on oral health habits, prior dental attendance patterns and the perceived general health status. RESULTS: Mean number of teeth present had a significant relationship with perceived health status. Implementation of particular oral health habits, such as using a toothbrush with nylon tufts and hard tufts, changing the toothbrush within three months, receiving tooth brushing instruction, scaling, and prompt dental treatment were related positively to the number of teeth present. Furthermore, the frequency of dental visits in the past showed an inverse relationship with the mean number of teeth present. This result does not necessarily mean, however, that regular dental visits are undesirable. From multiple regression, the mean number of teeth was calculated to be from 27.9 to 16.9 at 50 years of age and from 12.2 to 3.0 at 80 years of age in relation to oral health habits. CONCLUSIONS: To keep more teeth in the later years, it is evident that prevention of dental disease in earlier life is essential, and that individuals should receive prophylactic treatment, and maintain proper tooth brushing habits throughout life.

Clinical and experimental observation of glistening in acrylic intraocular lenses.

PURPOSE: To determine whether or not glistening particles in implanted acrylic intraocular lenses (IOL) increase with the passage of time. METHODS: Prospective clinical study: Glistenings were evaluated in 31 patients (49 eyes) with implanted acrylic IOL, the emphasis being on when glistening first became evident and subsequent changes in the number of glistening particles. EXPERIMENT: IOLs were monitored for any changes that occurred with the passage of time as they were immersed first in a 50 degrees C saline solution and then in another saline solution with a temperature of 35 degrees C. RESULTS: Prospective clinical study: Glistening phenomenon was observed in 28 IOLs (57%) 2 to 16 months after implantation (mean = 6.6 months). Glistenings reached their peak in number within a few months of formation in all cases, showing no further increase thereafter. EXPERIMENT: Glistening particles first appeared on the 10th day of the experiment in sizes ranging from 3 to 10 microm in diameter. They remained at the same level for the next 60 days without showing any increase. CONCLUSIONS: Glistening formation in acrylic IOLs was found to stabilize within a few months after appearance. The method of our experiment proved reliable in producing, in a relatively short period of time, glistening similar to that found in patients.

Application of a centrifugal shooting type polishing system to polish pure titanium.

Titanium is a difficult metal to grind, and thus mechanical polishing using conventional rotating tools takes a lot of time. The purpose of this study was to examine the polishing effect of a centrifugal shooting type polishing system on a pure titanium surface processed with a CAD/CAM system. The specimens' surfaces were polished for various times using this apparatus, then the center line average roughness (Ra) of each specimen was measured with surface roughness measuring apparatus. In addition, the surfaces after polishing were observed with a scanning electron microscope. After 50 sec of polishing, Ra decreased from 1.1 microns to less than 0.6 micron, and after 60 sec of polishing the cutting marks generated by the CAD/CAM system disappeared and a smooth surface was observed. Therefore, it appears that a centrifugal shooting type polishing system is effective at polishing pure titanium.

[The cause of polyurethane catheter cracking during constant infusion of etoposide (VP-16) injection].

We studied the cause of cracking of a clinically used polyurethane (PU) catheter during the constant infusion of etoposide (VP-16) injection (Lastet), administered without dilution to patients as a part of combination high-dose chemotherapy. After VP-16 injection was infused into the PU catheter at a constant infusion rate (30 ml/h) for 24 h, a decrease in the elasticity (36% of untreated) and on increase in the length of the catheter (3.7%) were observed. These changes were significantly higher than those treated with the control saline. The similar changes of the PU catheter were observed after treatment with a basal solution containing polyethylene glycol 400 (PEG 400), polysorbate 80 and ethanol, which is the vehicle of the VP-16 injection, and with ethanol alone. Moreover, obvious degeneration of the internal wall (occurrence of spots like melting) and cutting face (micro-cracking) of the catheter was observed with an electron microscope after treatment with the vehicle. On the other hand, the elasticity or extension of the PU catheter were not changed after treatment with saline or PEG 400. From these findings, it was suggested that the degeneration and subsequent cracking of the PU catheter during the infusion of VP-16 injection was caused by ethanol contained in its injection solution. No cracking or morphological changes of polyvinyl chloride (PVC) and silicone catheters were found after treatment with the vehicle solution. However, since it has been reported in previous reports that di(2-ethylhexyl)phthalate was leached from PVC bags, the high dose chemotherapy with the dilution-free VP-16 injection should be achieved safely and effectively using a silicon catheter, rather than the PU catheter.

[A case of stimulus-sensitive spinal myoclonus].

A 64-year-old man was admitted to our hospital because of a 2-year progression of muscular jerks on the bilateral thoracic and abdominal walls. Neurological examination was normal except for myoclonus localized in the bilateral Th5 to L1 segments. Myoclonus in this case was symmetrical and synchronous, and had a tendency to continue rhythmically. It was also segmental and considered to be spinal in origin. The interval between two adjacent myoclonic jerks was short when the amplitude and duration of the first myoclonus were high and long, respectively. We postulated that the activity of anterior horn cells at an impaired segment might be a factor that influences the resting time between jerks. A myoclonic jerk could be induced by a tendon tap given anywhere on this patient's body, with a latency ranging from 40 to 220 msec, irrespective of the sites of tapping. A long latency and polysynaptic reflex may participate in such stimulus sensitivity. The site of the reflex was probably above the motor nucleus of the trigeminal nerve, because jerks could be induced by jaw taps. Our observations support the theory that a spino-bulbo-spinal reflex is manifested at the impaired segment.

Examination of nerve distribution to masticatory muscles using a silicone permeation technique.

The detailed anatomical distribution of nerves throughout the human body has generally been studied by dissection of fixed cadavers in liquid. In this traditional method, it is difficult to maintain the position of nerves on their respective muscles. It is also difficult to keep the distributed form of the nerves. To understand the morphology of nerves, it is essential to determine their location and distribution precisely. In this study the masseter muscle was removed from a cadaver after fixation with formalin. The muscle was then permeated with silicone using the following procedure. The muscle fixed by 10% formalin was dehydrated with alcohol. After dehydration, alcohol was replaced with methylene chloride. The sample was permeated by silicone in a permeater. Following dissection, enamel was applied to the nerve by hand to fix its position. This new permeation method provided excellent localization of nerves innervating the muscle and has the added advantage of providing a three-dimensional structure of neural anatomy similar to the casting procedures used to visualize blood vessels.

[A case of pycnodysostosis].

Pycnodysostosis is a term introduced by Maroteaux and Lamy in 1962 to describe characteristic features such as dwarfism, separated cranial sutures, open fontanelles, hypoplasia and absence of mandibular angle, partial aplasia of the terminal phalanges of the fingers and toes, generalized condensation of bone shadow, bone fragility, and autosomal recessive inheritance. We reported a such case in a 13-years old boy associated with an epidural hematoma. Four weeks after removal of the hematoma, lumbar puncture was performed with the initial pressure of 200mm H2O in an awake state and the plateau waves were observed several times during sleep. Such increased intracranial pressure may have caused the open fontanelle and cranial sutures in addition to dysostosis. Thus such patients require careful attention in order to prevent major bleeding from the superior sagittal sinus directly beneath the separated sagittal suture.

[A case report of scimitar syndrome: a new technique in the correction of partial anomalous pulmonary venous drainage].

A twenty eight year-old man with anomalous pulmonary venous drainage from the right lung to the inferior vena cava (scimitar syndrome) underwent surgical treatment. We have successfully modified the surgical technique that consists of using the anterior wall of the right atrium, to form a tunnel that will divert the anomalous pulmonary vein to the left atrium. After rerouting of the anomalous pulmonary vein, the anterior wall of the right atrium was reconstructed with a polytetrafluoroethylene patch. To our knowledge, this is the first time this technique has been used to correct this syndrome.

[Assessment by means of a Minimum Data Set of the changes of mental and physical status of elderly patients with dementia during two years of institutionalization].

Using a Minimum Data Set, we studied how the mental and physical conditions of elderly people with dementia changed during two years of institutionalization. Fifty-five patients with dementia of Alzheimer's type (DAT) and 25 with vascular dementia (VD) admitted to the dementia ward in Kyoto Higashiyama Geriatric Hospital were investigated. We assessed them at the time of their institutionalization, and every three months for two years. On institutionalization, a difference between DAT and VD was noted in the group in which more than 10 areas of Resident Assessment Protocols (RAPs) were triggered. The areas of delirium, communication, behavioral problem, activities, activities of daily living, dehydration/fluid maintenance, and psychotropic drugs were evenly triggered in both dementia groups. In the DAT group, however, mood state and dental care were also highly triggered while urinary incontinence, falls and nutritional status were highly triggered in the VD group. Three months later, marked improvements were observed in all of the above areas. However, RAPs areas gradually increased subsequently, and there was marked difference in the areas and their course of progression between the dementia groups. In the DAT group, the trigger rate of the areas of communication, activities of daily living, urinary incontinence, dental care, nutritional status and falls gradually increased after 6 months of evaluation. However, the trigger rate in only three areas, such as communication, visual function and urinary incontinence, become higher, but their patterns of increase were irregular. Mental and physical conditions of the patients with dementia were different in each dementia subtype on institutionalization, but these conditions improved soon after. However, the conditions were gradually became worse, and the pattern was different in each dementia group: DAT showed a slow and steady decline, but VD showed irregular progression and differed among individuals.

[Improvements in mental and physical status of elderly patients with dementia after institutionalization--assessment with a minimum data set].

Using a Minimum Data Set, we studied how the mental and physical status of elderly people with dementia was modified by institutionalization. We assessed patients with dementia at the time of their admission in Kyoto Higashiyama geriatric hospital, and again three months later. On admission, both mental and physical problems were noted with a Resident Assessment Protocols. The former included cognitive loss/dementia, delirium, behavioral problem, activities, and mood state; the latter included visual function, activities of daily living (functional), urinary incontinence and indwelling catheter, nutritional status, dehydration/fluid maintenance, and dental care. Three months later, marked improvements were observed in 8 areas: delirium, psychological well-being, mood state, activities, urinary incontinence and indwelling catheter, nutritional status, dehydration/fluid maintenance and dental care. Cognitive loss/dementia and visual function were changed little. The unchanged areas were considered to be "core" manifestations of dementia, and those that changed were believed to reflect emotional problems and to be affected by the environment. Therefore, individualized care for elderly institutionalized patients with dementia should focus on these "peripheral" problems rather than on those that cannot be changed.

Two case reports of the right-sided aortic arch.

Two cases of right aortic arch with the left subclavian artery as its last branch were found in cadavers of 66- and 80-year-old Japanese males during the 1995 and 1996 dissection for students at Tokyo Dental College. In both cases, the esophagus and trachea were surrounded by a vascular ring which consisted of the aortic arch and arterial ligament. The left common carotid artery arose from the ascending aorta as the first branch and crossed ventral to the trachea in a left cephalic direction. In The second branch of the aorta, which was the right common carotid artery, the aortic arch ran in a dorsal direction, passing between the esophagus and vertebra after branch out the right subclavian artery. The left subclavian artery arose dorsal to the esophagus, and there was an aortic diverticulum between the left subclavian artery and the descending aorta. The arterial ligament communicated between the left pulmonary artery and the arterial diverticulum. The trachea and esophagus were consequently encircled by the vascular ring. Both of the present cases were of the N-type, according to the classification by Adachi-Williams-Nakagawa (Group IIIB1 type by Stewart, 1964).

A study of the internal structure of the Japanese mandible.

The thickness of the substantia compacta and the volume and width of the trabecular bone of the substantia spongiosa were investigated by soft X-ray photographs made of thin sections of many kinds of dentulous and edentulous mandibles. The results were: 1) The thickness of substantia compacta is especially thick on the lingual side in the incisor region and thickest in the molar region in all materials. At the base of mandible, the thickness is essentially the same in all regions, but, the thickness of dentulous materials is greater than of edentulous ones. 2) On the upper part, the volume of trabecular bone is less in the premolar region in both edentulous and dentulous material than in other regions, however, there is relative more in edentulous than in dentulous. In the central part, there is almost the same amount of trabecular bone in the dentulous and edentulous material. 3) The width of the trabecular bone in the substantia spongiosa is greater in the incisor region than in other regions in all materials. In the upper and central part, it is smaller in the premolar region in both edentulous and dentulous material but, it increases in the molar region in the edentulous materials.